> I guess a less extreme option would be for Microsoft to extend NT to be POSIX compliant...
Microsoft had this and abandoned it. I was building GNU software on NT in 2000 under Interix. It became Services for Unix and then was finally abandoned.
By WSL1. But WSL2 is a VM running a Linux kernel, not POSIX compatibility for Windows.
There's still all kinds of pain and werodness surrounding the filesystem boundary with WSL2. And contemporary Windows still has lots of inconsistency when trying to use Unix-style paths (which sometimes work natively and sometimes don't), and Unix-y Windows apps are still either really slow or full of hacks to get semi-decent performance. Often that's about Unix or Linux expectations like stat or fork, but sometimes other stuff (see for instance, Scoop's shim executable system that it uses to get around Windows taking ages to launch programs when PATH is long).
WSL2 also just isn't a real substitute for many applications. For instance, I'd like to be able to use Nix to easily build and install native Windows software via native toolchains on Windows machines at work. You can't do such a thing with WSL2. For that you need someone who actually knows Windows to do a Windows port, and by all reports that is very different from doing a port to a Unix operating system.
Idk if what people are asking for when they say 'POSIX compliant' with respect to Windows really has much to do with the POSIX standard (and frankly I don't think that matters). But they're definitely asking for something intelligible and real that Windows absolutely lacks.
> But they're definitely asking for something intelligible and real that Windows absolutely lacks.
Interix was what Windows lacks, but it was abandoned. It wasn't a Linux compatibility layer like WSL1 (or just a gussied-up Linux VM like WSL2). It was a freestanding implementation of POSIX and building portable software for it was not unlike building software portable to various *nixes. GNU autotools had a target for it. I built software from source (including upgrading the GCC it shipped with).
It was much more elegant than WSL and was built in the spirit of the architecture of NT.
IIRC Interix was a separate "subsystem" in the Windows API model - psxss.exe, with Win32 covered by csrss.exe and believe it or not there was an OS2 one.
What does it say about the practical usefulness of this Windows facility that MS has, it seems, never maintained one of these 'personalities' long-term?
There was a lot in the air in the early 90's when Windows NT was born - it wasn't a given that Windows, Intel, or heck even TCP/IP were going to be the tech mainstays they are today. So the whole "subsystem" thing is part of some seriously good long term strategic planning, though you know it was defintely to have one foot out of the door if their partnership with IBM went south, which it did.
> What does it say about the practical usefulness of this Windows facility that MS has, it seems, never maintained one of these 'personalities' long-term?
I am no defender of MICROS~1 but I think this is a misrepresentation.
1. Win32 is an NT personality and it is still actively maintained after 31 years.
2. Win16 ran on NTVDM which arguably is tantamount to a personality, and that is still present and works in Windows 10 32-bit today.
3. Downvotes or not, I stand by my point: the original POSIX personality became Windows Services for Unix, which went through 4 releases: 1.0, 2.0, 3.0, and 3.5.
But WSU was effectively a proprietary x86-32 Unix. Those are all dead and gone now, Xinuos notwithstanding, and having such a tool is no use in C21.
So, it was axed 20Y ago. 12Y later it was replaced by WSL.
WSL 1 was replaced by WSL2, and I mourn its lost potential. I feel WSL1 should have become a proper NT personality, which would have resulted in some improvements to Windows' capabilities.
My question was genuine, not just rhetorical. I appreciate the additional context here, especially that Win32 is implemented as a long-lived NT personality. It's indeed a bummer that Microsoft didn't see it as expedient to maintain the others or continue to grow WSL1.
Windows Services for Unix was also longer-lived than I'd realized. Was that just before its time or did it have some other problem?
I think it's probably business case and revenue potential, not practical usefulness. I felt like Interix was plenty useful but probably couldn't earn its keep. I think that pluggable personalities even exists in NT speaks to the general Microsoft embrace / extend / extinguish methodology. They were a means to an end to win contracts.
Microsoft had this and abandoned it. I was building GNU software on NT in 2000 under Interix. It became Services for Unix and then was finally abandoned.